apache2 problem

Having switched ISP, I am having problems with my webserver (LAMP -
Debian Sarge, Apache2). It used to work like a charm with my old ISP and all I changed is the first ServerName entry (which I copied from my IPCops main page).

Setting up the server while connected via my previous ISP, I found out
that with virtual hosting you always have to have the hostname for the
IP-address of the server first in the file which sets the virtual
hosts. My modem is in bridged mode, so the IP-address and the hostname
is passed on to the 'red' Ethernet card on my IPCop firewall, which is
set to DHCP. The IP-address is 84.245.34.233, the hostname is
84-245-34-233.dsl.cambrium.nl

I can ping all hostnames and IP-addresses (the internal IP-address of
my server as well). I think it must be some DNS-related problem, but I
haven't got a clue how to solve it.

<Directory /var/www/>
Options Indexes FollowSymLinks MultiViews
AllowOverride None
Order allow,deny
allow from all
# This directive allows us to have apache2's default start page
# in /apache2-default/, but still have / go to the right place
RedirectMatch ^/$ /apache2-default/
</Directory>

...snip...
WARN TCP Allowed WARNING: One or more of your DNS servers does not
accept TCP connections. Although rarely used, TCP connections are
occasionally used instead of UDP connections. When firewalls block the
TCP DNS connections, it can cause hard-to-diagnose problems. The problem
servers are:

212.79.232.3: Timeout. 195.245.199.130: Timeout. 212.79.243.3: Timeout.
WARN Single Point of Failure WARNING: Although you have at least 2 NS
records, there is a chance that they may both point to the same server
(one of our two tests shows them being different, the other is unsure;
it appears that there are one or more firewall(s) that intercept and
alter DNS packets (some versions of Linux reportedly have a built-in
firewall that does this, too)), which would result in a single point of
failure. You are required to have at least 2 nameservers per RFC 1035
section 2.2.
/...snip...

########## Begin - Rewrite rules to block out some common exploits
## If you experience problems on your site block out the operations listed below
## This attempts to block the most common type of exploit `attempts` to Joomla!
#
# Block out any script trying to set a mosConfig value through the URL
RewriteCond %{QUERY_STRING} mosConfig_[a-zA-Z_]{1,21}(=|\%3D) [OR]
# Block out any script trying to base64_encode crap to send via URL
RewriteCond %{QUERY_STRING} base64_encode.*\(.*\) [OR]
# Block out any script that includes a <script> tag in URL
RewriteCond %{QUERY_STRING} (\<|%3C).*script.*(\>|%3E) [NC,OR]
# Block out any script trying to set a PHP GLOBALS variable via URL
RewriteCond %{QUERY_STRING} GLOBALS(=|\[|\%[0-9A-Z]{0,2}) [OR]
# Block out any script trying to modify a _REQUEST variable via URL
RewriteCond %{QUERY_STRING} _REQUEST(=|\[|\%[0-9A-Z]{0,2})
# Send all blocked request to homepage with 403 Forbidden error!
RewriteRule ^(.*)$ index.php [F,L]
#
########## End - Rewrite rules to block out some common exploits

However www.sailmaster.nl/index.php gets me the homepage. Where in the Apache2 configuration can I solve this and how? To get php pages processed I had to uncomment some things in /etc/apache2/mods-enabled/php4.conf which I had commented first as described the HowTo:

Thanks for helping me, not just here on the forum, but with your HowTo's as well. They have enabled me to host small scale web-, ftp- and mailservices on a discarded office PC for a club which has no budget at all!